See our European project to study bottom-up and top-down forces in leaf herbivory of oak trees. Webpage
Understanding insularity effects on plant-herbivore interactions to promote insular biodiversity conservation PID2022-141761OB-I00) 2023-2026
Theory and early empirical work posed that herbivore pressure should be weaker on islands than on mainland owing to lower herbivore abundance and diversity in insular systems. Consequently, plant taxa found on islands are expected to be less defended or have even evolved the complete loss of defences. While early observational studies supported the prediction of lowered herbivory and plant defences on islands, recent island-mainland comparisons have shed mixed findings, with some studies showing no differences between islands and mainland or, surprisingly, higher herbivory and plant defences on islands. However, studies remain limited in scope both geographically and taxonomically and do not usually consider the multi-trophic contest in which plant-herbivore interactions are immersed. To address the paucity of studies, this proposal’s overall goal is to launch a global-scale assessment that moves beyond system- or regional-specific idiosyncrasies and identifies commonalities and differences across systems, and identifies underlying ecological correlates (biotic and abiotic factors) of observed patterns of herbivory and plant defences. We plan to achieve this by means of observational and experimental work in mainland-island sites which addresses the following features: (i) a broader geographical extent of island-mainland comparisons with site replication within each system and multiple systems (at both regional and global scales), (ii) a more comprehensive and integrative assessment of plant defensive phenotypes (multiple traits and their co-expression patterns), (iii) measurements of herbivory by vertebrate and invertebrate herbivores species and guilds, and (iv) a consideration of multi-trophic context in which plant-herbivore interactions are embedded, namely how predators respond to insularity and their relative influence on mainland vs. island herbivory and plant defences. By addressing the above, the proposed work seeks to reassess current theory and shed robust patterns with increased inference, with results boosting a new generation of studies on insularity effects on plant-herbivore interactions. Furthermore, results will be highly relevant in the context of insular biodiversity loss and ecosystem functionality by informing on insular plant and herbivore traits predictive of responses and susceptibility to human impacts and by identifying patterns of change in species interactions that relate to altered food web dynamics and reduced ecosystem function.
Theory and early empirical work posed that herbivore pressure should be weaker on islands than on mainland owing to lower herbivore abundance and diversity in insular systems. Consequently, plant taxa found on islands are expected to be less defended or have even evolved the complete loss of defences. While early observational studies supported the prediction of lowered herbivory and plant defences on islands, recent island-mainland comparisons have shed mixed findings, with some studies showing no differences between islands and mainland or, surprisingly, higher herbivory and plant defences on islands. However, studies remain limited in scope both geographically and taxonomically and do not usually consider the multi-trophic contest in which plant-herbivore interactions are immersed. To address the paucity of studies, this proposal’s overall goal is to launch a global-scale assessment that moves beyond system- or regional-specific idiosyncrasies and identifies commonalities and differences across systems, and identifies underlying ecological correlates (biotic and abiotic factors) of observed patterns of herbivory and plant defences. We plan to achieve this by means of observational and experimental work in mainland-island sites which addresses the following features: (i) a broader geographical extent of island-mainland comparisons with site replication within each system and multiple systems (at both regional and global scales), (ii) a more comprehensive and integrative assessment of plant defensive phenotypes (multiple traits and their co-expression patterns), (iii) measurements of herbivory by vertebrate and invertebrate herbivores species and guilds, and (iv) a consideration of multi-trophic context in which plant-herbivore interactions are embedded, namely how predators respond to insularity and their relative influence on mainland vs. island herbivory and plant defences. By addressing the above, the proposed work seeks to reassess current theory and shed robust patterns with increased inference, with results boosting a new generation of studies on insularity effects on plant-herbivore interactions. Furthermore, results will be highly relevant in the context of insular biodiversity loss and ecosystem functionality by informing on insular plant and herbivore traits predictive of responses and susceptibility to human impacts and by identifying patterns of change in species interactions that relate to altered food web dynamics and reduced ecosystem function.
Tritrophic interactions as drivers of insularity effects on insect herbivory and plant defences
EUR2023-143463 2023-2025
Theory and early empirical work posed that herbivore pressure should be weaker on islands than on mainland owing to lower herbivore abundance and diversity in insular systems. Consequently, plant taxa found on islands are expected to be less defended or have even evolved the complete loss of defences. While early observational studies supported the prediction of lowered herbivory and plant defences on islands, recent island-mainland comparisons have shed mixed findings, with some studies showing no differences between islands and mainland or, surprisingly, higher herbivory and plant defences on islands. However, previous studies remain do not usually consider the multi-trophic contest in which plant-herbivore interactions are immersed. To address this, this proposal’s overall goal is to consider the multi-trophic context in which plant-herbivore interactions are embedded, namely how predators respond to insularity and their relative influence on mainland vs. island herbivory and plant defences. By addressing the above, the proposed work seeks to reassess current theory and shed robust patterns with increased inference, with results boosting a new generation of studies on insularity effects on plant-herbivore interactions. Furthermore, results will be highly relevant in the context of insular biodiversity loss and ecosystem functionality by informing on insular plant and herbivore traits predictive of responses and susceptibility to human impacts and by identifying patterns of change in species interactions that relate to altered food web dynamics and reduced ecosystem function.
EUR2023-143463 2023-2025
Theory and early empirical work posed that herbivore pressure should be weaker on islands than on mainland owing to lower herbivore abundance and diversity in insular systems. Consequently, plant taxa found on islands are expected to be less defended or have even evolved the complete loss of defences. While early observational studies supported the prediction of lowered herbivory and plant defences on islands, recent island-mainland comparisons have shed mixed findings, with some studies showing no differences between islands and mainland or, surprisingly, higher herbivory and plant defences on islands. However, previous studies remain do not usually consider the multi-trophic contest in which plant-herbivore interactions are immersed. To address this, this proposal’s overall goal is to consider the multi-trophic context in which plant-herbivore interactions are embedded, namely how predators respond to insularity and their relative influence on mainland vs. island herbivory and plant defences. By addressing the above, the proposed work seeks to reassess current theory and shed robust patterns with increased inference, with results boosting a new generation of studies on insularity effects on plant-herbivore interactions. Furthermore, results will be highly relevant in the context of insular biodiversity loss and ecosystem functionality by informing on insular plant and herbivore traits predictive of responses and susceptibility to human impacts and by identifying patterns of change in species interactions that relate to altered food web dynamics and reduced ecosystem function.
Effects of global change drivers on Latin-American tropical dry forests: integrating research perspectives towards a more robust understanding and mitigation of impacts INCGL20004 2022-2024
Tropical dry forests (TDFs) are currently threatened by a number of global change drivers (e.g. drought, fire, insect outbreaks), and have been comparatively less studied than other terrestrial tropical ecosystems (e.g. tropical wet forests). Ecological research, including that on TDFs, has approached global change drivers from different perspectives. One line of research has focused on driver effects on species interactions without addressing ecosystem-level measurements (productivity, nutrient cycles, etc.), whereas another line of research has addressed impacts of drivers on ecosystem processes without looking at underlying changes in species interactions. Accordingly, these two lines of research have progressed largely independently, despite the need for integration to achieve a more robust scientific framework. The overall motivation of this proposal is to establish a collaboration between three groups (Biological Mission of Galicia, MBG-CSIC, Spain; Autonomous University of Yucatan, UADY, Mexico; Federal University of Lavras, UFLA, Brazil) with different and yet complementary backgrounds. The MBG-CSIC and UADY groups have approached TDF research from the perspective of driver effects on species interactions and their consequences for forest food webs. In contrast, the UFLA group has approached TDF research from the perspective of driver effects on tree community structure and ecosystem functions. The collaboration to be fostered by the proposed work seeks to link these research groups towards a more integrative science that bridges these perspectives and promotes a more robust understanding of global change driver effects on TDFs that improves conservation and impact mitigation.
Tropical dry forests (TDFs) are currently threatened by a number of global change drivers (e.g. drought, fire, insect outbreaks), and have been comparatively less studied than other terrestrial tropical ecosystems (e.g. tropical wet forests). Ecological research, including that on TDFs, has approached global change drivers from different perspectives. One line of research has focused on driver effects on species interactions without addressing ecosystem-level measurements (productivity, nutrient cycles, etc.), whereas another line of research has addressed impacts of drivers on ecosystem processes without looking at underlying changes in species interactions. Accordingly, these two lines of research have progressed largely independently, despite the need for integration to achieve a more robust scientific framework. The overall motivation of this proposal is to establish a collaboration between three groups (Biological Mission of Galicia, MBG-CSIC, Spain; Autonomous University of Yucatan, UADY, Mexico; Federal University of Lavras, UFLA, Brazil) with different and yet complementary backgrounds. The MBG-CSIC and UADY groups have approached TDF research from the perspective of driver effects on species interactions and their consequences for forest food webs. In contrast, the UFLA group has approached TDF research from the perspective of driver effects on tree community structure and ecosystem functions. The collaboration to be fostered by the proposed work seeks to link these research groups towards a more integrative science that bridges these perspectives and promotes a more robust understanding of global change driver effects on TDFs that improves conservation and impact mitigation.
Investigating plant-plant signaling via volatile organic compounds as a tool for sustainable management of cotton plantations in Mexico COOPA20477 2022-2023
Research has shown that plants perceive and respond to complex blends of above- or belowground VOCs emitted by conspecific or heterospecific neighbouring plants, a phenomenon termed “plant communication”. Such responses frequently involve either priming or induction of defences by “receiver” plants when exposed to incoming VOCs released by herbivore-damaged neighbours (“emitters”), which ultimately results in heightened resistance against herbivory. Plant communication has been documented in over 30 plant species, including several agricultural crops and forestry species, and is now a well-accepted phenomenon in plant defence research. In addition, during the last decade several authors have proposed agricultural management methods that make use of the exogenous application of VOCs to exploit plant communication mechanisms as a means of boosting crop protection against pests and diseases. Recent advances point at several key features that determine the strength of plant-plant signalling through VOCs, which can inform its application in agriculture. Notably, the total amount of volatiles emitted as well as the blends of compounds and abundance of individual compounds in volatile emissions depends on multiple biotic and abiotic factors, leading to specificity and context-dependency in plant communication. For example, communication appears to be strongly contingent upon the identity of the attacking herbivore, whereby different herbivores induce different volatile blends and induced resistance of plants exposed to VOCs might be only observed when emitter and receiver plants are attacked by the same insect. In addition, abiotic conditions can also influence plant volatile emissions, and therefore represent a potentially important source of variability in plant communication as shown by recent work reporting on water availability and salinity on plant-plant signalling. Together, these findings provide a first glimpse at the complexity and variability of plant communication, and point at important sources of specificity that may lead to predictable outcomes. Understanding the mechanisms and consequences of such specificity in both wild relatives or populations and cultivated varieties is a key aspect for exploiting plant-plant signalling via VOCs as a tool for sustainable crop management. By using experimental approaches combined with chemical and molecular measurements under greenhouse conditions, we seek to investigate the specificity and environmental context-dependency of VOCs-mediated communication in wild and cultivated cotton (Gossypium hirsutum) plants. Wild populations are especially abundant in Yucatan (Mexico), the likely center of origin of this species, therefore representing a key region and biological asset to inform cultivated cotton pest management. Accordingly, evaluating defensive mechanisms and signalling in both wild and cultivated genotypes will provide a broad assessment of variation in defences in this species, insight on domestication effects on quantitative and qualitative changes in defences, as well as the necessary knowledge base on differences between genotype sources needed to readily develop management and breeding practices for sustainable cotton production. In particular, we will test for wild and cultivated cotton specificity in communication with respect to herbivore identity and abiotic conditions (soil salinity), as well as the VOCs underlying any such effects.
Research has shown that plants perceive and respond to complex blends of above- or belowground VOCs emitted by conspecific or heterospecific neighbouring plants, a phenomenon termed “plant communication”. Such responses frequently involve either priming or induction of defences by “receiver” plants when exposed to incoming VOCs released by herbivore-damaged neighbours (“emitters”), which ultimately results in heightened resistance against herbivory. Plant communication has been documented in over 30 plant species, including several agricultural crops and forestry species, and is now a well-accepted phenomenon in plant defence research. In addition, during the last decade several authors have proposed agricultural management methods that make use of the exogenous application of VOCs to exploit plant communication mechanisms as a means of boosting crop protection against pests and diseases. Recent advances point at several key features that determine the strength of plant-plant signalling through VOCs, which can inform its application in agriculture. Notably, the total amount of volatiles emitted as well as the blends of compounds and abundance of individual compounds in volatile emissions depends on multiple biotic and abiotic factors, leading to specificity and context-dependency in plant communication. For example, communication appears to be strongly contingent upon the identity of the attacking herbivore, whereby different herbivores induce different volatile blends and induced resistance of plants exposed to VOCs might be only observed when emitter and receiver plants are attacked by the same insect. In addition, abiotic conditions can also influence plant volatile emissions, and therefore represent a potentially important source of variability in plant communication as shown by recent work reporting on water availability and salinity on plant-plant signalling. Together, these findings provide a first glimpse at the complexity and variability of plant communication, and point at important sources of specificity that may lead to predictable outcomes. Understanding the mechanisms and consequences of such specificity in both wild relatives or populations and cultivated varieties is a key aspect for exploiting plant-plant signalling via VOCs as a tool for sustainable crop management. By using experimental approaches combined with chemical and molecular measurements under greenhouse conditions, we seek to investigate the specificity and environmental context-dependency of VOCs-mediated communication in wild and cultivated cotton (Gossypium hirsutum) plants. Wild populations are especially abundant in Yucatan (Mexico), the likely center of origin of this species, therefore representing a key region and biological asset to inform cultivated cotton pest management. Accordingly, evaluating defensive mechanisms and signalling in both wild and cultivated genotypes will provide a broad assessment of variation in defences in this species, insight on domestication effects on quantitative and qualitative changes in defences, as well as the necessary knowledge base on differences between genotype sources needed to readily develop management and breeding practices for sustainable cotton production. In particular, we will test for wild and cultivated cotton specificity in communication with respect to herbivore identity and abiotic conditions (soil salinity), as well as the VOCs underlying any such effects.
Use of plant-plant communication through volatile organic compounds as a strategy for biological control of pests and diseases in potato plants RTI2018-099322-B-I00 2019-2021
Over three decades of work on airborne plant communication have demonstrated that plants send, receive, and respond to volatile organic compounds (VOCs) emitted by neighboring plants. Much of this research has focused on the consequences of plant-plant communication on resistance against herbivory, with studies showing that VOCs emitted by herbivore-damaged plants increase resistance of neighboring undamaged plants. This phenomenon of plant communication is thought to be widespread and an increasing number of studies have proposed the use of plant VOC-mediated signaling as an alternative for sustainable crop protection against pests and diseases. However, a key aspect that has received relatively less attention concerns the ecological specificity and context-dependency of this phenomenon. Knowledge on this is crucial for assessing the ecological mechanisms that govern plant communication, determining its biological significance under natural conditions, as well as designing effective strategies for its use in crop plant resistance. This project aim at evaluating the ecological specificity of plant communication, as well as the chemical mechanisms underlying this phenomenon, based on three main aspects: plant-based specificity, herbivore-based specificity, and the importance of the abiotic context.
Over three decades of work on airborne plant communication have demonstrated that plants send, receive, and respond to volatile organic compounds (VOCs) emitted by neighboring plants. Much of this research has focused on the consequences of plant-plant communication on resistance against herbivory, with studies showing that VOCs emitted by herbivore-damaged plants increase resistance of neighboring undamaged plants. This phenomenon of plant communication is thought to be widespread and an increasing number of studies have proposed the use of plant VOC-mediated signaling as an alternative for sustainable crop protection against pests and diseases. However, a key aspect that has received relatively less attention concerns the ecological specificity and context-dependency of this phenomenon. Knowledge on this is crucial for assessing the ecological mechanisms that govern plant communication, determining its biological significance under natural conditions, as well as designing effective strategies for its use in crop plant resistance. This project aim at evaluating the ecological specificity of plant communication, as well as the chemical mechanisms underlying this phenomenon, based on three main aspects: plant-based specificity, herbivore-based specificity, and the importance of the abiotic context.
Unravelling the mechanisms behind elevational gradients in plant-herbivore interactions. I-LINK1221 2018-2019
The study of elevational gradients in plant-herbivore interactions is still in its infancy, and a new generation of robust, empirical investigations based on a mechanistic framework are needed to consolidate the existing body of theory upon this relevant topic. The main goal of this proposal is to establish a professional relationship between the Misión Biológica de Galicia (MBG-CSIC) group and the foreign partner (BIOGECO, INRA, France) with the aim to develop a joint research proposal for upcoming funding calls from the European Union and the French government in the framework of elevational gradients in plant-herbivore interactions. Both teams investigate the same biological model (trees, e.g. oaks) and are highly interested in geographical variation in plant-animal interactions, albeit to date from different perspectives. While the MBG-CSIC group focuses on aspects of community ecology, chemical ecology and ecological gradients, the BIOGECO group works on aspects of molecular ecology and applied ecology. These different viewpoints offer an attractive opportunity for a successful and highly synergistic collaboration to deepen our knowledge on geographical variation in plant-herbivore interactions.
The study of elevational gradients in plant-herbivore interactions is still in its infancy, and a new generation of robust, empirical investigations based on a mechanistic framework are needed to consolidate the existing body of theory upon this relevant topic. The main goal of this proposal is to establish a professional relationship between the Misión Biológica de Galicia (MBG-CSIC) group and the foreign partner (BIOGECO, INRA, France) with the aim to develop a joint research proposal for upcoming funding calls from the European Union and the French government in the framework of elevational gradients in plant-herbivore interactions. Both teams investigate the same biological model (trees, e.g. oaks) and are highly interested in geographical variation in plant-animal interactions, albeit to date from different perspectives. While the MBG-CSIC group focuses on aspects of community ecology, chemical ecology and ecological gradients, the BIOGECO group works on aspects of molecular ecology and applied ecology. These different viewpoints offer an attractive opportunity for a successful and highly synergistic collaboration to deepen our knowledge on geographical variation in plant-herbivore interactions.
Factors influencing the direction and magnitude of altitudinal gradients in oak defensive strategies and herbivory. IN607D 2016/001 2016-2020
A traditional view of research on altitudinal gradients in species interactions holds that herbivory increases towards warmer and more stable climates found at lower altitudes, and this has led to greater defence levels in low-altitude plants relative to high-elevation plants. However, the generality of this expectation has been called into question by recent studies reporting no evidence of such trends or even positive altitudinal gradients in plant defence and herbivory. We argue that these mixed patterns have been due to unaccounted factors influencing plant defences and herbivory. In this project by using oaks as the study model we seek to present a comprehensive analysis of potential sources of controversy surrounding such altitudinal patterns. First, most studies have failed to test for the relative influence of abiotic factors (e.g. climate, soil variables) which may independently or concurrently shape plant defences and/or herbivory. Second, most studies have not separated between plant constitutive and induced defences or measured other plant defensive mechanisms such tolerance. Trade-offs between constitutive and induced defences or between tolerance and resistance are common so the lack of studies simultaneously measuring these multiple mechanisms of plant defence has likely hampered our understanding of altitudinal trends in plant-herbivore interactions. Third, most research on altitudinal gradients in plant defences and herbivory has considered plant defence as individual traits or strategies rather than the simultaneous expression of several defensive traits (i.e. defence syndromes). Broadly, this project builds towards a better understanding of altitudinal clines in plant-herbivore interactions and hopes to stimulate future studies explicitly addressing candidate biotic and abiotic factors contributing to such gradients.
A traditional view of research on altitudinal gradients in species interactions holds that herbivory increases towards warmer and more stable climates found at lower altitudes, and this has led to greater defence levels in low-altitude plants relative to high-elevation plants. However, the generality of this expectation has been called into question by recent studies reporting no evidence of such trends or even positive altitudinal gradients in plant defence and herbivory. We argue that these mixed patterns have been due to unaccounted factors influencing plant defences and herbivory. In this project by using oaks as the study model we seek to present a comprehensive analysis of potential sources of controversy surrounding such altitudinal patterns. First, most studies have failed to test for the relative influence of abiotic factors (e.g. climate, soil variables) which may independently or concurrently shape plant defences and/or herbivory. Second, most studies have not separated between plant constitutive and induced defences or measured other plant defensive mechanisms such tolerance. Trade-offs between constitutive and induced defences or between tolerance and resistance are common so the lack of studies simultaneously measuring these multiple mechanisms of plant defence has likely hampered our understanding of altitudinal trends in plant-herbivore interactions. Third, most research on altitudinal gradients in plant defences and herbivory has considered plant defence as individual traits or strategies rather than the simultaneous expression of several defensive traits (i.e. defence syndromes). Broadly, this project builds towards a better understanding of altitudinal clines in plant-herbivore interactions and hopes to stimulate future studies explicitly addressing candidate biotic and abiotic factors contributing to such gradients.
Factors determining the existence of defense syndromes in Quercus sps. in the Iberian Peninsula: consequences for the conservation of endangered species. AGL2015-70748-R 2016-2018
The Genus Quercus is represented by about 600 oak species around the world. In the Iberian Peninsula, this genus is represented by 14 tree species which exhibit contrasting leaf habits (evergreen, semi-evergreen and deciduous) and are distributed along most of the territory, from the sea level to 2,000 meters. Most of these species are of great economic importance due to the high quality of their wood for furniture production, their bark for cork production, as well as due to the acorns they produce which are used for human and animal consumption. Moreover, oak forests in the Iberian Peninsula are inhabited by a high number of endangered animal species. Despite their undeniable importance, the productivity of these oak forests and the viability of oak populations have declined considerably during recent decades due to global warming increased levels of attack by native and non-native (evolutionary novel) herbivores. To cope with these increased levels of herbivore attack as well as the presence of novel herbivores, plants make use of a diverse array of defensive traits. It is increasingly recognized that synergistic interactions between multiple defensive traits are common and likely provide higher levels of defense than would be achieved by the independent effects of each defensive trait. Accordingly, multiple defensive traits can be grouped in defense syndromes. Nonetheless, our understanding of plant defenses is largely reductionist and we still know very little about plant defense syndromes and thus the simultaneous effects of multiple plant defensive traits and their correlated evolution. Here, we propose to study defense syndromes across oak species inhabiting the Iberian Peninsula Specifically, we will carry out field and greenhouse experiments to investigate whether phylogeny, ontogeny, altitudinal gradients and their underlying biotic and abiotic drivers, leaf habit, and biogeography determine oak defense syndromes. In doing so, this project will advance our understanding of ecological and evolutionary aspects of plant of defensive mechanisms and will also generate key information that will serve in favor of conserving and managing Iberian oak populations. This will in turn provide substantial economic and social benefits.
The Genus Quercus is represented by about 600 oak species around the world. In the Iberian Peninsula, this genus is represented by 14 tree species which exhibit contrasting leaf habits (evergreen, semi-evergreen and deciduous) and are distributed along most of the territory, from the sea level to 2,000 meters. Most of these species are of great economic importance due to the high quality of their wood for furniture production, their bark for cork production, as well as due to the acorns they produce which are used for human and animal consumption. Moreover, oak forests in the Iberian Peninsula are inhabited by a high number of endangered animal species. Despite their undeniable importance, the productivity of these oak forests and the viability of oak populations have declined considerably during recent decades due to global warming increased levels of attack by native and non-native (evolutionary novel) herbivores. To cope with these increased levels of herbivore attack as well as the presence of novel herbivores, plants make use of a diverse array of defensive traits. It is increasingly recognized that synergistic interactions between multiple defensive traits are common and likely provide higher levels of defense than would be achieved by the independent effects of each defensive trait. Accordingly, multiple defensive traits can be grouped in defense syndromes. Nonetheless, our understanding of plant defenses is largely reductionist and we still know very little about plant defense syndromes and thus the simultaneous effects of multiple plant defensive traits and their correlated evolution. Here, we propose to study defense syndromes across oak species inhabiting the Iberian Peninsula Specifically, we will carry out field and greenhouse experiments to investigate whether phylogeny, ontogeny, altitudinal gradients and their underlying biotic and abiotic drivers, leaf habit, and biogeography determine oak defense syndromes. In doing so, this project will advance our understanding of ecological and evolutionary aspects of plant of defensive mechanisms and will also generate key information that will serve in favor of conserving and managing Iberian oak populations. This will in turn provide substantial economic and social benefits.
Mechanisms explaining tree species diversity effects on associated arthropod communities: patterns of insect herbivore dispersal and expression of plant chemical defenses. COOPB20158 2016-2017
Mixed forestry plantations represent an ideal strategy to increase tree productivity and improve wildlife conservation. Recent studies have reported increased productivity, lower rates of herbivore damage and greater diversity of associated fauna in multi-species plantations compared with monocultures of one species. Unfortunately, in tropical systems, particularly in Mexico, research on the effects of plant inter-specific diversity has lacked scientific rigor and ignored the underlying ecological processes. In 2012, Dr. Abdala-Roberts established a field experiment where we evaluate the effect of tree species diversity on plant growth and plant-herbivore interactions. The main goal of this proposal will be to improve this project by developing two new research lines. First, we will describe the spatial patterns of attack by insect herbivores with different dispersal ability and determine whether these patterns help to explain the effects of tree species diversity on them. Second, we will evaluate the effect of tree species diversity on chemical defenses and the extent to which these effects might mediate the response of insect herbivores to plant diversity.
Mixed forestry plantations represent an ideal strategy to increase tree productivity and improve wildlife conservation. Recent studies have reported increased productivity, lower rates of herbivore damage and greater diversity of associated fauna in multi-species plantations compared with monocultures of one species. Unfortunately, in tropical systems, particularly in Mexico, research on the effects of plant inter-specific diversity has lacked scientific rigor and ignored the underlying ecological processes. In 2012, Dr. Abdala-Roberts established a field experiment where we evaluate the effect of tree species diversity on plant growth and plant-herbivore interactions. The main goal of this proposal will be to improve this project by developing two new research lines. First, we will describe the spatial patterns of attack by insect herbivores with different dispersal ability and determine whether these patterns help to explain the effects of tree species diversity on them. Second, we will evaluate the effect of tree species diversity on chemical defenses and the extent to which these effects might mediate the response of insect herbivores to plant diversity.