Interactions between native insects and Australian invasive acacias in Europe Paiva, Maria-Rosa1,2, Silva, Pedro R. 1,, Ruas, Sara1, 1 Faculty of Sciences and Technology, Universidade Nova de Lisboa, 2829-516 Campus de Caparica, Portugal 2 CEF, ISA, Universidade Tecnica de Lisboa, 1349-017 Lisbon, Portugal Over 20 species of Australian acacias have been introduced in Europe, most of which became invasive and threaten the sustainability of native ecosystems. However, interactions between exotic acacias and the native entomofauna remain largely unstudied. Further, the role of exotic introduced insects involved in links of the food webs of native ecosystems, is also unknown. Research was conducted in Portugal, on Acacia longifolia and Acacia saligna, two of the most problematic invasive arboreal species in southern Europe. The composition of the communities of potential insect pollinators, associated with the acacias, was studied and comparisons made between the flowering and post-flowering periods. Although significantly more Hymenoptera and Coleoptera were caught when inflorescences were present, thus indicating that generalist pollinators likely promote seed production, their contribution to the invasive potential of A. longifolia should remain low. The role of ants in the dispersal of A. saligna seeds was also investigated. It was concluded that some common native ant species, particularly Aphaenogaster senilis and Messor barbarus, are efficient seed dispersers and promote the establishment of seed banks. Since acacia seeds may remain viable for decades, granivorous ants likely play an important role in their establishment and spread. By contrast, the exotic Argentine ant, Linepithema humile, that has invaded the coastal areas of Portugal, consumes the eliosomes of A. saligna seeds but do not translocate them, thus decreasing their fitness. Findings are innovative and uncover mutualistic relationships, presently evolving between native insects and exotic plants, which result in an adaptative advantage for the invaders.
|Title of host publication||XXIV International Congress of Entomology, 19-25 August, Daegu, S. Korea|
|Publication status||Published - 1 Jan 2012|
|Event||XXIV International Congress of Entomology, 19-25 August, Daegu, S. Korea - |
Duration: 1 Jan 2012 → …
|Conference||XXIV International Congress of Entomology, 19-25 August, Daegu, S. Korea|
|Period||1/01/12 → …|