Invasive and non-invasive congeneric Centaurea (Asteraceae) show contrasting patterns of herbivory by snails

• Autores: Filipe, João C.; Jorge, Andreia; Eren, Ozkan; Sotes, Gastón; Hierro, Jose Luis; Montesinos, Daniel
• Año de publicación: 2016
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: HERBIVORY; CHEMICAL DEFENCES; INVASIVE SPECIES; CENTAUREA
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

Background and aims – Once introduced into new regions, exotic species often experience shifts in resource allocation in response to the different environmental conditions found in the introduction range. Plants naturally respond to specialist herbivores with quantitative defences, by producing large amounts of toxic and non-toxic compounds that typically difficult digestion (e.g. tannins, cellulose), and to generalist herbivores with qualitative defences, like specialized noxious chemicals (e.g. alkaloids). The Shifting Defence Hypothesis (SDH) poses that invasive plants decrease the production of defences against specialist herbivores in their introduction range, where specialist herbivores are usually absent, while boosting the production of defences against generalist herbivores. Methods – We empirically assessed the response of a generalist herbivore, the common garden snail (Helix aspersa), to feeding with leaves of the annual herb Centaurea sulphurea, native to Europe and naturalized in North America; and the congeneric species C. solstitialis, which is also native to Europe and invasive in the Americas. Key results – Snails fed with leaves from Spanish native populations the non-invasive C. sulphurea grew significantly less compared to snails fed with leaves from non-native California. For snails fed with the invasive C. solstitialis significant differences were also found among regions, but the response was more complex, depending on population, with snails fed with Turkish and Australian plants presenting higher growth rates than the rest of the regions. Conclusions – Overall, our results stressed the importance of colonization history in shaping adaptive responses, and the stochasticity associated with colonization events of two closely related species, with contrasting invasive success and responses to herbivory.
Fil: Filipe, João C.. Universidad de Coimbra; Portugal
Fil: Jorge, Andreia. Universidad de Coimbra; Portugal
Fil: Eren, Ozkan. Adnan Menderes Universitesi; Turquía
Fil: Sotes, Gastón. Universidad de Concepción. Facultad de Ciencias Naturales y Oceanográficas. Departamento de Botánica; Chile. Universidad de Chile; Chile
Fil: Hierro, Jose Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; Argentina
Fil: Montesinos, Daniel. Universidad de Coimbra; Portugal