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Andrew G. Stephenson - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding in Solanum Carolinense alters floral attractants and rewards and adversely affects pollinator visitation
American journal of botany, 2021Co-Authors: Rupesh R Kariyat, Andrew G. Stephenson, Consuelo M De Moraes, Chad T. Nihranz, Thomas G. Bentley, Mark C MescherAbstract:PREMISE Inbreeding depression is well documented in flowering plants and adversely affects a wide range of fitness-related traits. Recent work has begun to explore the effects of inbreeding on ecological interactions among plants and other organisms, including insect herbivores and pathogens. However, the effects of inbreeding on floral traits, floral scents, and pollinator visitation are less well studied. METHODS Using inbred and outbred maternal families of horsenettle (Solanum Carolinense, Solanaceae), we examined the effects of inbreeding on traits associated with pollinator attraction and floral rewards. Specifically, we measured corolla size, counted pollen grains per flower, and analyzed floral volatile emissions via gas chromatography and mass spectrometry. We also examined pollinator visitation to experimental arrays of flowering inbred and outbred plants under field conditions. RESULTS Compared to those of outbred plants, flowers of inbred plants exhibited reduced corolla size and pollen production, as well as significantly reduced emission of the two most abundant volatile compounds in the floral blend. Furthermore, bumblebees-the main pollinators of horsenettle-discriminated against inbred flowers in the field: bees were more likely to make initial visits to flowers on outbred plants, visited outbred flowers more often overall, and spent more time on outbred flowers. CONCLUSIONS These results show that inbreeding can (1) alter floral traits that are known to mediate pollinator attraction; (2) reduce the production of floral rewards (pollen is the sole reward in horsenettle); and (3) adversely affect pollinator visitation under field conditions.
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Transgenerational impacts of herbivory and inbreeding on reproductive output in Solanum Carolinense.
American journal of botany, 2020Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, William S. Walker, Steven J. Brown, Andrew G. StephensonAbstract: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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Herbivory and inbreeding affect growth, reproduction, and resistance in the rhizomatous offshoots of Solanum Carolinense (Solanaceae)
Evolutionary Ecology, 2019Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, Rupesh R Kariyat, Rebecca L. Kolstrom, Andrew G. StephensonAbstract:Resource sharing within clonal plant networks can occur via the translocation of water, nutrients, and photoassimilates through rhizomes and stolons. Similar mechanisms may mediate the sharing of information (e.g., about herbivory or other environmental stressors) among ramets via molecular or biochemical signals. The storage of such information in belowground structures could facilitate the transmission of appropriate phenotypic responses across growing seasons in perennial species. However, few previous studies have explored the potential transfer of ecologically relevant information within such networks. This study addresses the effects of foliar herbivory and belowground overwintering on the growth and flowering, physical defenses, and herbivore resistance in the clonally spreading species Solanum Carolinense L. (Solanaceae). We used rhizomes from inbred and outbred plants that were repeatedly exposed to feeding damage by Manduca sexta L. (Sphingidae) caterpillars and rhizomes from undamaged control plants. These rhizomes were either planted immediately or exposed to overwintering conditions and allowed to produce new ramets (rhizomatous offshoots). We then assessed offshoot emergence, flowering, physical defense traits, and herbivore performance. Relative to controls, offshoots of herbivore-damaged plants exhibited greater spine and trichome densities, and reduced performance of M. sexta larvae. However, they also emerged and flowered significantly later, and produced fewer flowers than offshoots of undamaged plants. Inbreeding also negatively affected offshoot emergence, flowering, trichome production, and herbivore resistance. These effects of parental herbivory were more pronounced in outbred offshoots, indicating that inbreeding may compromise the trans-seasonal induction of plant defenses. Finally, exposure to overwintering conditions increased trichome production and reduced caterpillar performance on offshoots. Together, these results show that induced defenses can be transmitted through rhizomes and affect offshoot growth, flowering, defensive traits, and herbivore resistance. They also document fitness-related costs associated with defense induction in offshoots and suggest that the transfer of defenses across seasons can be compromised by inbreeding.
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non glandular trichomes of Solanum Carolinense deter feeding by manduca sexta caterpillars and cause damage to the gut peritrophic matrix
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Supplementary material from "Non-glandular trichomes of Solanum Carolinense deter feeding by Manduca sexta caterpillars and cause damage to the gut peritrophic matrix"
2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
Mark C Mescher - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding in Solanum Carolinense alters floral attractants and rewards and adversely affects pollinator visitation
American journal of botany, 2021Co-Authors: Rupesh R Kariyat, Andrew G. Stephenson, Consuelo M De Moraes, Chad T. Nihranz, Thomas G. Bentley, Mark C MescherAbstract:PREMISE Inbreeding depression is well documented in flowering plants and adversely affects a wide range of fitness-related traits. Recent work has begun to explore the effects of inbreeding on ecological interactions among plants and other organisms, including insect herbivores and pathogens. However, the effects of inbreeding on floral traits, floral scents, and pollinator visitation are less well studied. METHODS Using inbred and outbred maternal families of horsenettle (Solanum Carolinense, Solanaceae), we examined the effects of inbreeding on traits associated with pollinator attraction and floral rewards. Specifically, we measured corolla size, counted pollen grains per flower, and analyzed floral volatile emissions via gas chromatography and mass spectrometry. We also examined pollinator visitation to experimental arrays of flowering inbred and outbred plants under field conditions. RESULTS Compared to those of outbred plants, flowers of inbred plants exhibited reduced corolla size and pollen production, as well as significantly reduced emission of the two most abundant volatile compounds in the floral blend. Furthermore, bumblebees-the main pollinators of horsenettle-discriminated against inbred flowers in the field: bees were more likely to make initial visits to flowers on outbred plants, visited outbred flowers more often overall, and spent more time on outbred flowers. CONCLUSIONS These results show that inbreeding can (1) alter floral traits that are known to mediate pollinator attraction; (2) reduce the production of floral rewards (pollen is the sole reward in horsenettle); and (3) adversely affect pollinator visitation under field conditions.
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Transgenerational impacts of herbivory and inbreeding on reproductive output in Solanum Carolinense.
American journal of botany, 2020Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, William S. Walker, Steven J. Brown, Andrew G. StephensonAbstract: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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Herbivory and inbreeding affect growth, reproduction, and resistance in the rhizomatous offshoots of Solanum Carolinense (Solanaceae)
Evolutionary Ecology, 2019Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, Rupesh R Kariyat, Rebecca L. Kolstrom, Andrew G. StephensonAbstract:Resource sharing within clonal plant networks can occur via the translocation of water, nutrients, and photoassimilates through rhizomes and stolons. Similar mechanisms may mediate the sharing of information (e.g., about herbivory or other environmental stressors) among ramets via molecular or biochemical signals. The storage of such information in belowground structures could facilitate the transmission of appropriate phenotypic responses across growing seasons in perennial species. However, few previous studies have explored the potential transfer of ecologically relevant information within such networks. This study addresses the effects of foliar herbivory and belowground overwintering on the growth and flowering, physical defenses, and herbivore resistance in the clonally spreading species Solanum Carolinense L. (Solanaceae). We used rhizomes from inbred and outbred plants that were repeatedly exposed to feeding damage by Manduca sexta L. (Sphingidae) caterpillars and rhizomes from undamaged control plants. These rhizomes were either planted immediately or exposed to overwintering conditions and allowed to produce new ramets (rhizomatous offshoots). We then assessed offshoot emergence, flowering, physical defense traits, and herbivore performance. Relative to controls, offshoots of herbivore-damaged plants exhibited greater spine and trichome densities, and reduced performance of M. sexta larvae. However, they also emerged and flowered significantly later, and produced fewer flowers than offshoots of undamaged plants. Inbreeding also negatively affected offshoot emergence, flowering, trichome production, and herbivore resistance. These effects of parental herbivory were more pronounced in outbred offshoots, indicating that inbreeding may compromise the trans-seasonal induction of plant defenses. Finally, exposure to overwintering conditions increased trichome production and reduced caterpillar performance on offshoots. Together, these results show that induced defenses can be transmitted through rhizomes and affect offshoot growth, flowering, defensive traits, and herbivore resistance. They also document fitness-related costs associated with defense induction in offshoots and suggest that the transfer of defenses across seasons can be compromised by inbreeding.
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non glandular trichomes of Solanum Carolinense deter feeding by manduca sexta caterpillars and cause damage to the gut peritrophic matrix
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Supplementary material from "Non-glandular trichomes of Solanum Carolinense deter feeding by Manduca sexta caterpillars and cause damage to the gut peritrophic matrix"
2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
Rupesh R Kariyat - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding in Solanum Carolinense alters floral attractants and rewards and adversely affects pollinator visitation
American journal of botany, 2021Co-Authors: Rupesh R Kariyat, Andrew G. Stephenson, Consuelo M De Moraes, Chad T. Nihranz, Thomas G. Bentley, Mark C MescherAbstract:PREMISE Inbreeding depression is well documented in flowering plants and adversely affects a wide range of fitness-related traits. Recent work has begun to explore the effects of inbreeding on ecological interactions among plants and other organisms, including insect herbivores and pathogens. However, the effects of inbreeding on floral traits, floral scents, and pollinator visitation are less well studied. METHODS Using inbred and outbred maternal families of horsenettle (Solanum Carolinense, Solanaceae), we examined the effects of inbreeding on traits associated with pollinator attraction and floral rewards. Specifically, we measured corolla size, counted pollen grains per flower, and analyzed floral volatile emissions via gas chromatography and mass spectrometry. We also examined pollinator visitation to experimental arrays of flowering inbred and outbred plants under field conditions. RESULTS Compared to those of outbred plants, flowers of inbred plants exhibited reduced corolla size and pollen production, as well as significantly reduced emission of the two most abundant volatile compounds in the floral blend. Furthermore, bumblebees-the main pollinators of horsenettle-discriminated against inbred flowers in the field: bees were more likely to make initial visits to flowers on outbred plants, visited outbred flowers more often overall, and spent more time on outbred flowers. CONCLUSIONS These results show that inbreeding can (1) alter floral traits that are known to mediate pollinator attraction; (2) reduce the production of floral rewards (pollen is the sole reward in horsenettle); and (3) adversely affect pollinator visitation under field conditions.
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Herbivory and inbreeding affect growth, reproduction, and resistance in the rhizomatous offshoots of Solanum Carolinense (Solanaceae)
Evolutionary Ecology, 2019Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, Rupesh R Kariyat, Rebecca L. Kolstrom, Andrew G. StephensonAbstract:Resource sharing within clonal plant networks can occur via the translocation of water, nutrients, and photoassimilates through rhizomes and stolons. Similar mechanisms may mediate the sharing of information (e.g., about herbivory or other environmental stressors) among ramets via molecular or biochemical signals. The storage of such information in belowground structures could facilitate the transmission of appropriate phenotypic responses across growing seasons in perennial species. However, few previous studies have explored the potential transfer of ecologically relevant information within such networks. This study addresses the effects of foliar herbivory and belowground overwintering on the growth and flowering, physical defenses, and herbivore resistance in the clonally spreading species Solanum Carolinense L. (Solanaceae). We used rhizomes from inbred and outbred plants that were repeatedly exposed to feeding damage by Manduca sexta L. (Sphingidae) caterpillars and rhizomes from undamaged control plants. These rhizomes were either planted immediately or exposed to overwintering conditions and allowed to produce new ramets (rhizomatous offshoots). We then assessed offshoot emergence, flowering, physical defense traits, and herbivore performance. Relative to controls, offshoots of herbivore-damaged plants exhibited greater spine and trichome densities, and reduced performance of M. sexta larvae. However, they also emerged and flowered significantly later, and produced fewer flowers than offshoots of undamaged plants. Inbreeding also negatively affected offshoot emergence, flowering, trichome production, and herbivore resistance. These effects of parental herbivory were more pronounced in outbred offshoots, indicating that inbreeding may compromise the trans-seasonal induction of plant defenses. Finally, exposure to overwintering conditions increased trichome production and reduced caterpillar performance on offshoots. Together, these results show that induced defenses can be transmitted through rhizomes and affect offshoot growth, flowering, defensive traits, and herbivore resistance. They also document fitness-related costs associated with defense induction in offshoots and suggest that the transfer of defenses across seasons can be compromised by inbreeding.
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non glandular trichomes of Solanum Carolinense deter feeding by manduca sexta caterpillars and cause damage to the gut peritrophic matrix
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Supplementary material from "Non-glandular trichomes of Solanum Carolinense deter feeding by Manduca sexta caterpillars and cause damage to the gut peritrophic matrix"
2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Plant inbreeding and prior herbivory influence the attraction of caterpillars (Manduca sexta) to odors of the host plant Solanum Carolinense (Solanaceae).
American journal of botany, 2014Co-Authors: Rupesh R Kariyat, Andrew G. Stephenson, Mark C Mescher, Sarah R. Scanlon, Ryan P. Moraski, Consuelo M De MoraesAbstract: Premise of this study: The mediation of plant–insect interactions by plant odors has been studied extensively, but most previous work has focused on documenting the role of constitutive and herbivore- or pathogen-induced plant volatiles as foraging cues for insect herbivores and their natural enemies. Relatively little work has explored genotypic variation in plant-odor profi les within species, and few studies have addressed the perception and use of olfactory cues by lepidopteran larvae or other herbivores during feeding. Methods: We examined the effects of plant breeding (inbred vs. outbred individuals) and plant exposure to prior herbivory on the preferences of caterpillars ( Manduca sexta ) for odors of Solanum Carolinense in leaf-disc and whole-plant choice assays. Key results: Second- and third-instar larvae of M. sexta clearly and consistently preferred undamaged over herbivore-damaged plants of both breeding types and also consistently preferred inbred over outbred plants that had the same damage status. Similar preferences were observed even when plants were covered with bridal-veil cloth to mask visual cues, demonstrating that olfactory cues infl uence larval preferences. Conclusions: The observed preferences are consistent with our previous fi ndings regarding the constitutive and induced volatile profi les of inbred and outbred horsenettle plants and their effects on plant–herbivore interactions. They furthermore correspond to differences in host-plant quality predicted by previous work and, thus, suggest that naive larvae of M. sexta can accurately assess aspects of host-plant quality via olfactory cues perceived at a distance.
Consuelo M De Moraes - One of the best experts on this subject based on the ideXlab platform.
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Inbreeding in Solanum Carolinense alters floral attractants and rewards and adversely affects pollinator visitation
American journal of botany, 2021Co-Authors: Rupesh R Kariyat, Andrew G. Stephenson, Consuelo M De Moraes, Chad T. Nihranz, Thomas G. Bentley, Mark C MescherAbstract:PREMISE Inbreeding depression is well documented in flowering plants and adversely affects a wide range of fitness-related traits. Recent work has begun to explore the effects of inbreeding on ecological interactions among plants and other organisms, including insect herbivores and pathogens. However, the effects of inbreeding on floral traits, floral scents, and pollinator visitation are less well studied. METHODS Using inbred and outbred maternal families of horsenettle (Solanum Carolinense, Solanaceae), we examined the effects of inbreeding on traits associated with pollinator attraction and floral rewards. Specifically, we measured corolla size, counted pollen grains per flower, and analyzed floral volatile emissions via gas chromatography and mass spectrometry. We also examined pollinator visitation to experimental arrays of flowering inbred and outbred plants under field conditions. RESULTS Compared to those of outbred plants, flowers of inbred plants exhibited reduced corolla size and pollen production, as well as significantly reduced emission of the two most abundant volatile compounds in the floral blend. Furthermore, bumblebees-the main pollinators of horsenettle-discriminated against inbred flowers in the field: bees were more likely to make initial visits to flowers on outbred plants, visited outbred flowers more often overall, and spent more time on outbred flowers. CONCLUSIONS These results show that inbreeding can (1) alter floral traits that are known to mediate pollinator attraction; (2) reduce the production of floral rewards (pollen is the sole reward in horsenettle); and (3) adversely affect pollinator visitation under field conditions.
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Transgenerational impacts of herbivory and inbreeding on reproductive output in Solanum Carolinense.
American journal of botany, 2020Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, William S. Walker, Steven J. Brown, Andrew G. StephensonAbstract: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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Herbivory and inbreeding affect growth, reproduction, and resistance in the rhizomatous offshoots of Solanum Carolinense (Solanaceae)
Evolutionary Ecology, 2019Co-Authors: Chad T. Nihranz, Mark C Mescher, Consuelo M De Moraes, Rupesh R Kariyat, Rebecca L. Kolstrom, Andrew G. StephensonAbstract:Resource sharing within clonal plant networks can occur via the translocation of water, nutrients, and photoassimilates through rhizomes and stolons. Similar mechanisms may mediate the sharing of information (e.g., about herbivory or other environmental stressors) among ramets via molecular or biochemical signals. The storage of such information in belowground structures could facilitate the transmission of appropriate phenotypic responses across growing seasons in perennial species. However, few previous studies have explored the potential transfer of ecologically relevant information within such networks. This study addresses the effects of foliar herbivory and belowground overwintering on the growth and flowering, physical defenses, and herbivore resistance in the clonally spreading species Solanum Carolinense L. (Solanaceae). We used rhizomes from inbred and outbred plants that were repeatedly exposed to feeding damage by Manduca sexta L. (Sphingidae) caterpillars and rhizomes from undamaged control plants. These rhizomes were either planted immediately or exposed to overwintering conditions and allowed to produce new ramets (rhizomatous offshoots). We then assessed offshoot emergence, flowering, physical defense traits, and herbivore performance. Relative to controls, offshoots of herbivore-damaged plants exhibited greater spine and trichome densities, and reduced performance of M. sexta larvae. However, they also emerged and flowered significantly later, and produced fewer flowers than offshoots of undamaged plants. Inbreeding also negatively affected offshoot emergence, flowering, trichome production, and herbivore resistance. These effects of parental herbivory were more pronounced in outbred offshoots, indicating that inbreeding may compromise the trans-seasonal induction of plant defenses. Finally, exposure to overwintering conditions increased trichome production and reduced caterpillar performance on offshoots. Together, these results show that induced defenses can be transmitted through rhizomes and affect offshoot growth, flowering, defensive traits, and herbivore resistance. They also document fitness-related costs associated with defense induction in offshoots and suggest that the transfer of defenses across seasons can be compromised by inbreeding.
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non glandular trichomes of Solanum Carolinense deter feeding by manduca sexta caterpillars and cause damage to the gut peritrophic matrix
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Supplementary material from "Non-glandular trichomes of Solanum Carolinense deter feeding by Manduca sexta caterpillars and cause damage to the gut peritrophic matrix"
2017Co-Authors: Rupesh R Kariyat, Jason D Smith, Andrew G. Stephenson, Consuelo M De Moraes, Mark C MescherAbstract:Plant trichomes constitute a first line of defence against insect herbivores. The pre- and post-ingestive defensive functions of glandular trichomes are well documented and include direct toxicity, adhesion, antinutrition and defence gene induction. By contrast, the defensive functions of non-glandular trichomes are less well characterized, although these structures are thought to serve as physical barriers that impede herbivore feeding and movement. We experimentally varied the density of stellate non-glandular trichomes in several ways to explore their pre- and post-ingestive effects on herbivores. Larvae of Manduca sexta (Sphingidae) initiated feeding faster and gained more weight on Solanum Carolinense (Solanaceae) leaves having lower trichome densities (or experimentally removed trichomes) than on leaves having higher trichome densities. Adding trichomes to artificial diet also deterred feeding and adversely affected caterpillar growth relative to controls. Scanning electron and light microscopy revealed that the ingestion of stellate trichomes by M. sexta caterpillars caused extensive damage to the peritrophic membrane, a gut lining that is essential to digestion and pathogen isolation. These findings suggest that, in addition to acting as a physical barrier to deter feeding, trichomes can inhibit caterpillar growth and development via post-ingestive effects.
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Diffuse interactions between two herbivores and constraints on the evolution of resistance in horsenettle (Solanum Carolinense)
Arthropod-Plant Interactions, 2010Co-Authors: Michael J. WiseAbstract:Interactions between plants and herbivores are considered “diffuse” if the ecological interactions between two species, or their evolutionary responses, differ depending on the presence of a third species. I looked for evidence of diffuse interactions among horsenettle ( Solanum Carolinense ) and two common herbivores. Plants experimentally protected from lace bugs ( Gargaphia solani ) were twice as susceptible to attack from flea beetles ( Epitrix fuscula ) once transplanted into the field. Thus, the selective benefit to horsenettle of resistance against lace bugs in nature would likely be diminished by increased attack from flea beetles. Moreover, the relative rank among horsenettle genotypes for resistance against flea beetles was changed by prior exposure to lace bugs. Thus, the genetic expression of resistance to flea beetles would depend on the “lace bug environment.” By affecting selective pressures or response to selection, these sorts of diffuse interactions in a plant-herbivore community can slow the host plant’s evolution of resistance to its herbivores.
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Herbivores affect natural selection for floral-sex ratio in a field population of horsenettle, Solanum Carolinense
Ecology, 2010Co-Authors: Michael J. Wise, Julie B. HébertAbstract:Although aspects of a plant's breeding system are generally believed to have evolved in response to selection for effective pollination, herbivores may also play a selective role. Here we report on a field experiment involving 960 transplanted ramets of the andromonoecious herb Solanum Carolinense in which the pattern of natural selection for an important breeding-system trait was influenced by naturally occurring herbivores. As the level of flower and fruit herbivory increased, the pattern of selection on floral-sex ratio went from stabilizing (with an optimum of 29% male flowers), to directional toward a lower proportion of males, with the optimum bottoming at 0% male. This pattern of selection likely helped generate the broad-sense genetic correlation (r = 0.42) between floral-sex ratio and resistance to herbivory. These results contribute to the growing awareness that herbivores can be important influences not only on plant resistance traits, but also on the evolution of their hosts' breeding system.
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Compensation for floral herbivory in Solanum Carolinense: identifying mechanisms of tolerance
Evolutionary Ecology, 2008Co-Authors: Michael J. Wise, Jeremiah J. Cummins, Cassandra YoungAbstract:While a plant’s capacity to tolerate damage by herbivores can be studied as a single trait, it is important to recognize that tolerance is generally a result of the combined action of several different traits. Here, we report on a pair of experiments to identify mechanisms for tolerating floral herbivory in Solanum Carolinense , an andromonoecious perennial herb that regularly suffers from high levels of florivory. We measured the effect of actual and simulated florivory on host-plant fitness and assessed which plant traits exhibited plasticity in response to florivory. In addition, for each of nine plant genets, we calculated tolerance indices and determined which traits were genetically correlated with tolerance. Traits that served to help S. Carolinense tolerate florivory in terms of sexual reproduction included initiating more inflorescences, aborting fewer buds prior to anthesis and fewer ovaries after fertilization, and increasing the ratio of perfect:male flowers. In addition, the greater the levels of florivory, the more the plants allocated to root growth, which may promote tolerance through greater potential future reproduction. The plant population contained significant genetic variation for tolerance itself and for nearly all of the putative tolerance mechanisms, which suggests that S. Carolinense has the potential to evolve greater tolerance through a variety of different routes in response to natural selection.
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The Herbivores of Solanum Carolinense (Horsenettle) in Northern Virginia: Natural History and Damage Assessment
Southeastern Naturalist, 2007Co-Authors: Michael J. WiseAbstract:Abstract I studied interactions between the herbaceous weed Solanum Carolinense (horsenettle) and its herbivore community in northern Virginia from 1996–2002. Thirty-two species regularly fed on the plant, including 31 insects from 6 taxonomic orders and Microtus pennsylvanicus (meadow vole). An intensive field experiment on 960 horsenettle individuals in 2001 revealed high levels of damage to all parts of the plants. Two chrysomelid beetles—Epitrix fuscula (eggplant flea beetle) and Leptinotarsa juncta (false potato beetle)—damaged leaves on nearly every plant. Roughly half of the flowers were destroyed by herbivores, with Anthonomus nigrinus (potato bud weevil) destroying 30%. Nearly three-fourths of the fruits were damaged by three species: the tephritid fly Zonosemata electa (pepper maggot), false potato beetle, and meadow vole. The weevil Trichobaris trinotata (potato stalk borer) bored in stems of 73% of the plants, and the most damaging root feeder was the moth Synanthedon rileyana (Riley's clearwi...
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Evolutionary ecology of resistance to herbivory: an investigation of potential genetic constraints in the multiple-herbivore community of Solanum Carolinense.
The New phytologist, 2007Co-Authors: Michael J. WiseAbstract:Summary • As part of a study of the ecological and evolutionary dynamics of herbivore resistance in Solanum Carolinense (horsenettle), potential genetic constraints to the evolution of resistance to 11 of its most common herbivores were investigated. • Leaf, flower, fruit, and stem herbivory were measured in a field experiment involving 24 ramets of each of 40 horsenettle genets. • The experimental plant population contained significant genetic variation for resistance to all 11 species of herbivore. For only one species was there an indication of a genotype-by-environment interaction in the expression of resistance that might constrain its evolution. Genetic correlations in resistance to different species were common but not universal, with seven negative and 12 positive correlations out of the 55 pairwise species comparisons. Correlations were independent of plant part fed upon. • The evolution of the resistance of horsenettle to most of its diverse community of herbivores does not appear to be prevented by a lack of genetic variation or by genotype-by-environment interactions in resistance. Negative genetic correlations in resistance to different herbivores may play a small role in slowing the evolution of resistance, but positive correlations may play at least as large a role in facilitating its evolution.