Geographical variation in alkaloid production in Conium maculatum populations experiencing differential herbivory by Agonopterix alstroemeriana

Conium maculatum, a Eurasian weed naturalized in North America, contains high concentrations of piperidine alkaloids, which act as chemical defenses against herbivores. In the United States, C. maculatum was largely free from herbivory until approximately 30 years ago, when it was re-associated via...

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Detalles Bibliográficos
Autores: Castells, Eva|||0000-0001-7423-2742, Berhow, M. A., Vaughn, S. F., Berenbaum, May|||0000-0003-3165-8385
Tipo de recurso: artículo
Fecha de publicación:2005
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:16222803
Acceso en línea:https://ddd.uab.cat/record/125703
https://dx.doi.org/urn:doi:10.1007/s10886-005-5921-x
Access Level:acceso abierto
Palabra clave:Insect-plant interactions
Conium maculatum
Agonopterix alstroemeriana
Chemical defenses
Alkaloids
γ-coniceine
Coniine
Conhydrinone
Evolution
Herbivory
Descripción
Sumario:Conium maculatum, a Eurasian weed naturalized in North America, contains high concentrations of piperidine alkaloids, which act as chemical defenses against herbivores. In the United States, C. maculatum was largely free from herbivory until approximately 30 years ago, when it was re-associated via accidental introduction with a monophagous European herbivore, the oecophorid caterpillar Agonopterix alstroemeriana. At present, A. alstroemeriana is found in a continuum of re-association time and intensities with C. maculatum across the continent; in the Pacific Northwest, A. alstroemeriana can cause severe damage, resulting in some cases in complete defoliation. Studies in biological control and invasion biology have yet to determine whether plants re-associated with a significant herbivore from the area of indigeneity increase their chemical defense investment in areas of introduction. In this study, we compared three locations in the U.S. (New York, Washington and Illinois) where C. maculatum experiences different levels of herbivory by A. alstroemeriana to determine the association between the intensity of the interaction, as measured by damage, and chemical defense production. Total alkaloid production in C. maculatum was positively correlated with A. alstroemeriana herbivory levels; plants from New York and Washington, with higher herbivory levels, invested two and four times more N to alkaloid synthesis than did plants from Illinois. Individual plants with lower concentrations of alkaloids from a single location in Illinois experienced more damage by A. alstroemeriana, suggestive of a preference on the part of the insect for plants with less chemical defense. These results suggest that A. alstroemeriana may act either as a selective agent or inducing agent for C. maculatum and increase its toxicity in its introduced range.