Phytophagous insect fauna tracks host plant responses to exotic grass invasion

Autor(es)

Almeida-Neto, Mario ^{[1, 2]} ; Prado, Paulo I. ^[3] ; Lewinsohn, Thomas M. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Brasilia UnB, Inst Ciencias Biol, Dept Ecol, BR-70919970 Brasilia, DF - Brazil

^[2] Univ Estadual Campinas UNICAMP, Inst Biol, Curso Posgrad Ecol, Campinas, SP - Brazil

^[3] Univ Sao Paulo, Inst Biociencias, Dept Ecol, BR-05508900 Sao Paulo - Brazil

^[4] Univ Estadual Campinas UNICAMP, Inst Biol, Dept Biol Anim, Lab Interacoes Insetos Plantas, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Oecologia; v. 165, n. 4, p. 1051-1062, APR 2011.
• Citações Web of Science: 18

Resumo

The high dependence of herbivorous insects on their host plants implies that plant invaders can affect these insects directly, by not providing a suitable habitat, or indirectly, by altering host plant availability. In this study, we sampled Asteraceae flower heads in cerrado remnants with varying levels of exotic grass invasion to evaluate whether invasive grasses have a direct effect on herbivore richness independent of the current disturbance level and host plant richness. By classifying herbivores according to the degree of host plant specialization, we also investigated whether invasive grasses reduce the uniqueness of the herbivorous assemblages. Herbivorous insect richness showed a unimodal relationship with invasive grass cover that was significantly explained only by way of the variation in host plant richness. The same result was found for polyphagous and oligophagous insects, but monophages showed a significant negative response to the intensity of the grass invasion that was independent of host plant richness. Our findings lend support to the hypothesis that the aggregate effect of invasive plants on herbivores tends to mirror the effects of invasive plants on host plants. In addition, exotic plants affect specialist insects differently from generalist insects; thus exotic plants affect not only the size but also the structural profile of herbivorous insect assemblages. (AU)

• Processo FAPESP: 06/56889-2 - Diversidade e estrutura de interações tritróficas num gradiente de degradação antrópica: plantas, herbívoros e parasitóides em áreas de cerrado
• Beneficiário: Mário Almeida Neto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 04/15482-1 - Interacoes planta-herbivoro: matrizes de associacoes e suas respostas a perturbacoes.
• Beneficiário: Thomas Michael Lewinsohn
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 98/05085-2 - Diversidade e interação de espécies em plantas e insetos fitófagos
• Beneficiário: Thomas Michael Lewinsohn
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOTA - Temático